1. Field of the Invention
The present invention relates to a communication device having a radio communication function, a communication system thereof, and a communication setting method thereof.
2. Description of the Related Art
In recent years, the number of home electronic devices corresponding to wireless Local Area Network (LAN) is being increased (hereinafter, these electronic devices are sometimes referred to as wireless LAN connectable devices). Wireless LAN connectable devices include printers and digital cameras that correspond to wireless LAN. In addition, as a broadcast content distributing system, a visual audio system that allows the user to watch and listen to television broadcasts regardless where he or she is, namely that has place shift function has been commercialized with a name of location free (registered trademark of Sony Corporation). The minimum structure of the place shift visual audio system is a base station that is a content transmitting device disposed in the user's house and a receiving device that provides a video and an audio to him or her who watches and listens to them (these devices are also referred to as a location free player or a client).
When the base station and a television antenna are connected, the user can watch and listen to a television broadcast program that is on air in any room of the house using a wireless communication function of the base station in real time. If a device such as a DVD recorder or a hard disk recorder is connected to the base station, a video and an audio reproduced by the device can be wirelessly (radio) transmitted. In addition, the television broadcast program received by the base station is converted into a digital signal. Video and audio are compressed by Moving Picture Experts Group phase 2 (MPEG2), Advanced Video Coding (AVC) (H. 264), or MPEG4 and Advanced Audio Coding (AAC), MPEG audio, or the like, respectively, in real time. The compressed data are retransmitted through the Internet. The user can watch and listen to a video and an audio with a receiving device that decompresses the received compressed data anywhere outside the house or in a foreign country.
Receiving devices include mobile devices such as portable game machines, Personal Digital Assistants (PDAs), note type personal computers (hereinafter sometimes referred to as note PCs), portable liquid crystal monitors, and portable phones (in which appropriate application software has been installed). In addition, using a receiving device that outputs received broadcast content as a video output to a television receiver, this device is called a TV box (trade name of Sony Corporation), the user can watch and listen to the broadcast program with an ordinary television receiver.
As one connection form, the base station functions as an access point and the receiving device is connected as a client (called the station) to the base station on wireless LAN. In this case, the base station is connected to the Internet through a router and a broadband modem. However, since the connection point to the Internet in the house may be apart from the base station, it may be difficult to connect them with a cable. Thus, the base station has a switch that switches the build-in LAN function from the access point to the station.
In other words, if an access point of wireless LAN has been disposed at the connection point to the Internet in the house, the base station can be newly added as a station. In this case, wireless LAN is an infrastructure. To allow a wireless LAN connectable device to radio-communicate with wireless LAN, it is necessary to perform various settings for the device. Generally, these settings include searching for Service Set Identifier (SSID) (input of an SSID character string in the case of stealth), selection of an encryption system, input of an encryption key character string). These operations are very bothersome and complicated. These information necessary for wireless LAN connection is referred to as connection setting information.
SSID is a character string that is set to each access point and that identifies a party of wireless LAN. When the same SSID is set to an access point and a station or both to stations, they can communicate with each other. SSID is standardized as Institute of Electrical and Electronics Engineers (IEEE) 802.11. IEEE 802.11 describes Wired Equivalent Privacy (WEP) as an encrypting function. As an encryption system that compensates vulnerabilities of WEP, Temporal Key Integrity Protocol has been standardized.
Japanese Patent Application Laid-Open No. 2007-36733 (Patent Document 1) describes a method of setting connection setting information of wireless LAN. In addition, Japanese Patent Application Laid-Open No. 2007-74556 (Patent Document 2) describes a simple setting method of copying connection setting information of a personal computer using a cable (eg, Universal Serial Bus (USB) cable).